1. Field of the Invention
The invention relates to mainframe computer printing, particularly with respect to pixel addressable printers such as non-impact and matrix printers. The invention specifically concerns creation and modification of fonts, electronic forms, sketches and page compositions.
2. Description of the Prior Art
Printing at mainframe computer facilities had in the past been effected by impact printers. Impact printers utilized fixed character sets or fonts determined by the printer hardware such as the print bands, chains or wheels and only one font was selectable at a time. Changing the hardware in order to change the font was an arduous task. With impact printers, new character sets could only be added to the facility by new printer hardware. New characters could not be added to existing character sets, new characters could not be created nor could existing characters be modified in such systems. Additionally, in impact printer facilities, when it was desired to print on predetermined forms, traditionally suchg forms were preprinted and utilized for the applications as required. If it became necessary to modify a form, it was necessary to have new forms printed, discarding the supply of the obsolete forms. This is an undersirably wasteful procedure. It had been possible, however, to embed the form generation within the application programs and to modify the application to accommodate changes in the forms. This procedure required each page on which a form was to be utilized to be separately coded in the applcation and transferred to the printer at the time of print execution. This placed an undesirable overhead on the system and also required the use of skilled programmers to modify the applications to accommodate desired form changes.
With the advent of non-impact printers, such as laser printers, at mainframe computer facilities, many of the disadvantages of impact printers have been overcome but the enhanced capabilities and flexibility provided by pixel programmable printers are not easily accessible to and useable by non-technical persons. At present day mainframe computer facilities with laser printing, a wide variety of character arrangements and fonts are available to facility users. Additionally, at some facilities, electronic forms that may be invoked and overlayed on the pages during printing are available in the facility library to the applications run on the system.
It is desirable at such facilities to provide the capability of creating and modifying character arrangements, sets and fonts which would be available to existing applications. It is also desirable to create and modify the electronic forms, the form overlays, page compositions, and to provide graphics such as signatures and logos. In present day facilities, such functionality may only be accomplished by skilled system programmers who are required to prepare complex programs involving manually converting characters and forms into hexidecimal data bytes and adhering to a rigid structure and protocol. Because of the difficulty involved, users generally do not utilize this available functionality but instead revert to prior techniques such as preprinted forms and graphics. Additionally, the prior art utilities for such purposes tend to be poorly supported and documented.
In addition to the above, special publishing software packages are available that provide some of the functionality discussed above such as, electronic forms, logos, signatures, and page compositions, at mainframe computer facilities. Such publishing software, however, require the application programs that wish to utilize the software to be specially coded so to do. As far as it goes, this approach provides desirable functionality but would require users to write new applications or rewrite existing applications to access the capability. From a user's viewpoint, this is undersirable in that it involves an inordinately large investment in order to create and modify their application programs which may be extremely extensive and expensive.